Needle cooler

ABSTRACT

A needle cooler for a sewing machine with a vortex tube producing a cold air and hot air stream, a mounting block for mounting the cooler on a sewing machine with a bore connected to the vortex tube for transmitting the cold air to a nozzle via a flexible plastic tube, and an L-shaped positioning rod extending through bores in the block and nozzle for positioning the nozzle in a desired orientation with set screws engaging the rod in the bores for holding the nozzle in the desired orientation.

The present invention relates to a device for cooling a needle of a sewing machine.

Particularly at high speed operation, heating of sewing machine needles has produced numerous problems, particularly in commercial use. The heating of the needle produces thread breakage, clogged needle eyes, skipping and lost production time. In order to avoid these problems, it has been conventional to treat thread with silicone lubricant. However, such lubricants are expensive and do not entirely prevent thread breakage and skipping resulting from heating of the needle.

The present invention relates to a simple and effective needle cooler which directs a flow of frigid air onto the needle. The needle cooler, according to the present invention, utilizes a conventional vortex tube to produce a stream of cold air. The cooler further includes a mounting block for easily and conveniently mounting the cooler onto a sewing machine, a nozzle which directs the cool air onto the needle, a flexible tube connecting the block outlet to the nozzle, and a manually adjustable positioning rod connecting the mounting block and the nozzle. Utilizing a flexible tube, preferably of plastic, permits the tube to be twisted to any desired orientation of the nozzle, and also permits ready adjustment of the tube length by cutting to fit any desired sewing machine. The positioning rod is a simple and effective way to position the nozzle to direct the cold air as desired onto the nozzle. The rod is preferably L-shaped and extends between the block and nozzle with the horizontal portion extending through a bore in the nozzle and being held in place by a set screw and the vertical portion extending through a bore in the block and also being held in place by a set screw.

Many other objects and purposes of the invention will be clear from the following detailed description of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a view of the unique cooler of the present invention mounted on a conventional sewing machine;

FIG. 2 shows a plan view of the cooler of the present invention;

FIG. 3 shows a side view of the cooler of the present invention;

FIG. 4 shows an end view of the cooler of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Reference is now made to FIGS. 1-4 which illustrate the unique nozzle of the present invention. Referring to FIG. 1, the nozzle 20 is shown mounted on a conventional sewing machine 22. Because of the use of the positioning rod and flexible tube, the cooler 20 can be mounted on any commercial sewing machine to direct flow to the needle as desired.

Referring to FIGS. 2-4, pressurized gas from a suitable source 30 such as is conventionally available in the environment of a commercial sewing machine is applied to an inlet 32 of a vortex tube 34. Vortex tube 34 is a conventional device which is described in detail, for example, in U.S. Pat. No. 3,208,229. Accordingly, no detailed discussion of the vortex tube is believed appropriate here except to note that it produces separate streams of hot and cold gas. In the present invention, the hot gas leaves the vortex tube at an outlet 36 and is conducted vertically upward to leave the cooler by a tube 38. The vortex tube may be made of any suitable material such as aluminum. The cold air outlet 40 of vortex tube 34 is connected by a suitable threaded fitting to an aluminum block 42 having a bore 44 extending therethrough. The cold air stream generated by vortex tube 34 passes through bore 44 to an outlet 46 of the mounting block 42.

Mounting block 42 includes a further bore 50 for accommodating screws which mount block 42 and the cooler 20 onto a sewing machine as generally indicated in FIG. 1.

A hollow nozzle 54 which may be made of aluminum or the like includes a bore 56 through which the cold air moves to be injected onto a needle. A flexible tube 58, preferably made of plastic, connects the outlet 46 to the inlet 60 of the nozzle 54. The plastic tube can be cut to any size desired or required for a given sewing machine.

L-shaped rod 64 permits the nozzle 54 to be oriented in any desired position and to be held in that orientation. Rod 64 includes a vertical portion extending through a bore 66 in mounting block 42, and a set screw 68 engages the rod 64 within bore 66 to lock the rod in a given orientation. The horizontal portion of rod 64 extends through a bore 70 in nozzle 54 and is held in position by a set screw 72 which engages rod 64 in that bore. Rod 64 is preferably metal.

Many changes and modifications in the abovedescribed embodiment of the invention can, of course, be carried out without departing from the scope of the invention. Accordingly, that scope is intended to be limited only by the scope of the appended claims. 

What is claimed is:
 1. A needle cooler for a sewing machine comprising:a vortex tube having an inlet for connection to a source of pressurized gas, a cold air outlet and a hot air outlet; a block mounting said tube having a bore extending therethrough from an inlet coupled to said cold air outlet to a block outlet, said block including means for mounting said cooler on a sewing machine; a nozzle for directing cold air onto a sewing machine needle; a flexible tube connecting said block outlet to said nozzle; and a manually adjustable positioning rod extending between said block and said nozzle for positioning and holding said nozzle in an orientation so that said nozzle directs said cold air onto said needle.
 2. A cooler as in claim 1, wherein said rod has an L-shape with a vertical portion extending through a second bore in said block and a horizontal portion extending through a bore in said nozzle and including a first set screw engaging said rod in said second bore and a second set screw engaging said rod in said nozzle bore.
 3. A cooler as in claim 1, wherein said rod is metal and said tube is plastic.
 4. A cooler as in claim 1, further including a metal outlet tube connected to said hot air outlet. 